Dave Walker, a Canadian journalist and filmmaker, who was trying to track down the Khmer Rouge for a documentary, has been declared missing since 14 February.

Canadian journalist and film-maker Dave WalkerFindDaveWalker.com

Canadian journalist and film-maker Dave WalkerFindDaveWalker.com

Walker, 58, was last seen leaving his guesthouse in Siem Reap to allow a housekeeper to clean his room. He is said have gone out without passport, phone, laptop and other belongings.

Walker's friends have now set up a website to help find the journalist.

As part of his documentary, Walker was trying to trace the Khmer Rouge officials and had already met several artists, who were tortured under the regime.

According to his website, Walker co-founded Cambodian-registered company Animist Farm Films in July 2012, to produce "high-concept, human interest" films and revive the country's movie industry.

Walker's close friend Peter Vronksky, who has started a Facebook page to create awareness on his disapperance, wondered whether Walker had been "silenced" by someone who felt threatened by his efforts to trace the Khmer Rouge.

"I spoke with Dave's ex-wife Praiwan this morning. She was aware of Dave's disappearance and attempted to file a report with police in Canada early in the week, but was unaware of the joint effort underway. Her worry was as ours, whether Canadian officials are going to take this seriously. She is convinced that Dave got into a vehicle with somebody he knew and trusted. Her words exactly were, nobody could have "taken down Dave." At least not without a bloody mess...." said Vronksky.

Richard E. Erlich, another close friend of Walker, said: "It all sounds very grim, but it also sounds very weird that he disappeared entirely."

During the 1970s, the Khmer Rouge waged a genocide in Cambodia, killing more than a million people as it tried to impose hardline communist ideology in the country. Several Khmer Rouge supporters have gone on trial in recent years.

The fear among many is that the Khmer Rouge may have had a hand in Walker's disappearance.

For providing any update on the missing journalist, please visit: Find Dave Walker.